Vulcanizing press



NOV. 20, H E R E VULGANIZING PRESS Filed June 29, 1932 '7 Sheets-Sheet 1Filed June 29, 1932 7 Sheets-Sheet 2 gwwntov Herman E. Norse Nov. 20,1934. MORSE 1,981,628

VULCANIZING PRESS Filed June 29, 1932 7 Sheets-Sheet 3 smut oz HermanLT/Yons NOV. 20, 1934. H E o s 1,981,628

VULCANIZING PRESS Filed June 29, 1932 7 Sheets-Sheet 4 Herman 5 H m Nov.20, 1934. V MORSE 1,981,628

VULCANI z IN'G PRESS Filed June 29, 1932 7 Sheets-Sheet 6 1 gwuenbo cHerman E Morse NOV. 20, 1934. H E, MORSE VULCANIZING PRESS Filed June29, 1932 '7 Sheets-Sheet '7 gwve tot Herman E Norse Patented Nov. 20,193? t I t v t UNITED STATES PATENTHOFFI'CE VULCANIZING PRESS Herman E.Morse, Akron, Ohio, assignor to Wingfoot Corporation, Wilmington, Del.,a corporation of Delaware Application June 29, 1932, Serial No. 619,8577 8 Claims. (01. 18-17) This invention relates to presses, and more Fig.4 is a transverse cross-sectional view particularly to vulcanizingpresses for curing rubtaken on line IV-IV of Fig. 1; berized material,such as flat conveyor belting, Fig. 5 is a perspective view of the rightend of together with means for stretching the rubberized the machineillustrated in Fig. 1; 1

5 material prior to the vulcanizing operation. Fig. 6 is across-sectional view taken on line An object of the invention is toprovide an im- VI--VI oiFig. 2; p proved vulcanizing press. Fig. '7 is aview taken on line VII--VII of Fig. 6;

Another object of the invention is to produce Fig. 8 is across-sectional view taken on line a vulcanizing press having means forstretching VIII-VIII of Fig. "7 g g i L55. lo the material prior to thevulcanizing operation, Fig. 9 is a diagrammatic side elevationilluscapable of producing a flat and excellent product trating hydraulicmeans for coordinating the which will not grow in service. 7 stretcherand press platens;

Another object of the invention is to provide Fig. 10 is asideelevational view illustrating stretching means which are in correctalignment mechanical means for securing di ti b with the materialstretched. tween the stretcher and press platens; and Another object ofthe invention is to provide Fig. 11 is an end elevation of the mechanisma vulcanizing press with stretching means which shown in Fig. 10. aremounted upon independent foundations so While the apparatus embodyingthe present that the stretching operation is achieved without inventioncan be employed in the manufacture of 20 any fi s-a g nt 0 the press pThis substantially any vulcanizable or heat treated construction alsoacts to prevent deformation of article as will be understood, it isparticularly h press platens w h the resulting unequal p adapted tovulcanize fiat rubberized fabric consure over the surfaces thereof.veyor belts. -Accordingly the vulcanizing press An h r object of h inv ni n i t pr vi has been illustrated and described in conjunction 25 avulcanizing press with independently mounted ith nveyor belting,stretching pp so that h vuloenizing press Referring to the drawings, thevulcanizing and particula y the ends t o a easily press embodying thepresent invention comprises cessible at all times. a base 15, to whichan upper platen 16 is rigidly An h r object f h inv n i is to vi asecured by 'a plurality of tie rods 17. Mounted 1. 30' vulc Dress Withmaterial Stretching means upon .the base 15.- are a plurality; ofhydraulic Which a independent of the p and t0 P motors 20, havingpistons 21, which carry a lower vide coordinating apparatus therebetweenso that platen 22 Mounted between the upper platen 16 the ve e t of thePress platens Will cause a and the lower platen 22 is an intermediateplaten corresponding movement of the stretching means. 23 hi hooperateswith the upper platen 16 35' An h r object of h inv n i n is top v to mold and vulcanizeabelt 28. The lower platen hydraulic means forsimultaneously mOvil'lg the 22 cooperates with the middle platen 23 tomold stretching means up and down in coordination and vulcanize b lt 27,Th th platens are with the movement of the press platens, so thatbrought together by an upwa,rd mo ement of the belt will be held awayfrom'the hot press the lower platen The middle gg; is

'40- pla s w the vuloenizine operation is not n supported in a positionintermediate of the upper progress I platen 16 and the lower platen 22by any suita- Another object of the invention is to provide m I meanswhen t press is open Multiple mechanical means for coordinating themovement platen presses of t geheral t are t new of the stretcher andvulcanizing press platens.- per S and it is believed t general construe-For a better understanding of the invention tion and operation thereofwill be understood by reference may now be had to the accompanying thoseshined in the t r I drawings, Whereim If the sides of the belt orbelts'are to be molded 1 is a Side elevation with a Portion 0f the orshaped during the curing operation'flat bars or center thereof removed,illustrating the press and plates are provided b t th platens which 50 st i mechanism dyi the p s nt incan be moved in from the sides of theplatens by Vehtion; wedge means to clamp on the sides or the belts. Fig.2 is a. plan view of the mechanism illus- This apparatus is more or lesswell known in'the trated i art and forms no part of the presentinvention. v

' Fig. 3 is a transverse cross-sectional view'taken In order to insurefiat stretched belts'during 01111116 III-4H of the vulcanizingoperation, and also to substantially eliminate any future growth in thebelt,

stretching means are provided to stretch the belts prior to and duringthe curing operation. To this end clamping means are provided at one endof the press platens to grip the upper belt 28, while stretching meansare provided at the other end. With respect to the lower belt 27, theclamping means are provided at the end of the platensopposite that wherethe upper belt is clamped, while the stretching means for the lower beltare provided at the clamping end of the upper belt. In the presentinvention the stretch ing means includes frames 30 and 31, which aremounted upon the base 15 independently of the means 17 and 20 supportingthe platens '16, 22 and 23 and which are secured at their upper ends tolongitudinally extending channel irons 32. The frame 30 supports aclamping .unit, indicated generally at 33, which is adapted to clamp onone end of the lower belt 27.

Referring to Fig. 4, the clamping mit 33 includes a cross-head35 whichis slidably gibbed to the frame 30 by gibs 36. Hydraulic motors 38mounted upon the frame 30 control the vertical position of thecross-heads 35, inasmuch as the piston rods 39 of the hydraulic motors38 are secured to the cross-heads 35. A lower clamping jaw 41 is securedbetween the cross-heads 35 by any suitable means, such as pins 42.Mounted upon the upper ends of the cross-heads 35 by tie rods43 arehydraulic motors 44, the piston rods 45 of which extend down throughsuitable aper tures in the upper end of the cross-heads 35 and whichserve to carry an upper clamping jaw 46 which cooperates with the lowerclamping jaw 41 I to clamp the belt 27 therebetween.

jaw 41 will be level vertical position. I

Small auxiliary hydraulic motors 50 having piston rods 51 are secured tothe tops of the motors 44. The piston rods 51 of the hydraulic 'motors50 areprovided with Spreaders 52, to the ends of which are secured tierods 53, which'extend down through the tie rods 43 fastening thehydraulic motors 44 to the cross-heads 35 and which are secured at theirends to the upper clamping member 46. The hydraulic motors 44 will thusserve to clamp the upper jaw member 46 against the lower jaw 41, whilethe hydraulic motors 50 will serve to move the upper jaw 46 upwardlywhen it is desired to unclamp or release the belt.

In order to have the same movementat all times at both ends of the lowerjaw member 41, and to thus maintain it perfectly horizontal, racks 57(Fige 'l) may be secured to the sides of the frame 30, which rackscooperate with pinions 58 carried upon the ends of a shaft 59, which is'journaled atits ends, in suitable bearing plates 60 secured to thecross-heads 35. In this manner the cross-heads 35 and the lower clampingat all times regardless of their At the same end of the vulcanizingpress as the unit 33 for clamping the end of the belt 27 is a unitindicated generally at 65 for clamping on and, stretching the upperbeltt28. Referring to" Figs. 1 and 3, the clamping and stretching unit65 includes-frames 66 mounted uponthe base 15 and secured at their upperends to the channels 32, which frames 66 slidably support cross-headmembers 67 through the agency of gibs 68. Hydraulic motors '70 havingpiston rods 71 are mounted upon the frames 66 and control the verticalposition of the cross-heads 67, inasmuch as. thepiston rods 71 of thehydraulic motors 70 are secured to the lower sides of the cross-heads67.

The vertical positions of the cross-heads 67 may be kept the samethrough the agency of racks 73 secured upon the frame 66, which rackscooperate with pinions 74 carried upon a shaft 75 journaled in suitablebrackets 76 secured to the cross-heads 67. This mechanism is similar indesign and function to that described above with respect to the meansfor synchronizing the movement of the cross-heads 35 of the clampingunit .Slidably mounted in suitable grooves 80 in the cross-head members67 is a lower clamping member 8,1. Secured to the lower clamping jaw 81atthe ends. thereof are frame members 82 to which are secured hydraulicmotors 83, which in turn support hydraulic motors 84. The hydraulicmotors 83 have pistons 86, which extend down through suitable apertures87 in the members 82, and which are secured to an upper clamping jaw 90.Thehydraulic motors 84 have piston rods 92, which are secured to theirends to spreaders 93 carrying tie rods 94, which extend down and aresecured to the upper clamping jaw 90. In this manner the hydraulicmotors 83 serve to move the clamping jaw downwardly againstthe clampingjaw 81, while the hydraulic motors 84 serve to raise the jaw 90 awayfrom the jaw 81 when it is desired to unclamp or release the belt 28. i

The horizontal position of the clamping jaws 81 and 90, theframe members82, and the hyof hydraulic motors 96, the piston rods 97 of which aresecured to the clamping jaw 81. The s cylinders of the hydraulic motors96 are secured bysuitable tie rods 98 to the cross-heads 67 In orderthat the cross-heads 35 and 67 can be moved vertically while the beltsare under tension between the various clamping means ed upon the lowerclampingjaw 81. This mechanism serves to unify the operation of thehydraulic motors 96 and insures that the jaw members 81 and 90 move inand out at both sides thereof equal distances.

At the otherendof thepress, upon the framework 31, is mounted a clampingunit indicated generally by the numeral 110, which serves to clamp theend of the belt 28 and thus cooperate with the clamping and stretchingunit 65. Cooperating with the clamping unit 33 is a clamping andstretching unit which is indicated as a whole at 115,. and which ismounted upon a suitable frame 118 secured to the base 15 and channeliron 32; The units 115 and 110 are exactly similar to the units 33 and65, except that they are placed at the other end ofthe belt and that thestationary clamping unit 110 is placed above the clamping and stretchingunit 115. Accordingly the various elements forming the clamping unit 110and the clamping and'stretching unit 115 are designated with the samenumerals which indicate similar parts in the clamping unit 33and glO "ing unit 33.

the clamping and stretching unit 65, except that the suflix a has beenadded.

The various hydraulic motors employed in the apparatus are connected inany suitable manner to an adequate source of hydraulic pressure. To thisend conduits 120, 121, 122, 123 and 124, valved as hereafter described,extend to hydraulic motors 70, 38, 20, 38 and Conduits 126 and 127 areconnected to the motors 44, 83, 44 83" and 50, 84, 50 and 84respectively by way of swivel connections 128 and 129. Hand valves (notshown) control the passage of fluid through the conduits, the valvesbeing placed in a convenient position for operation. The motors 96 and96 are provided with fluid pressure by means of swivel connections 116extending from two way valves 117 connected to supply conduits 118.

The movements of the platens 22, 23 and 16 are adapted to be coordinatedwith the vertical movements of the clamping and the clamping andstretchingunits 33, 65, and 115, and this can be accomplished by eithermechanical or hydraulic means. The diagrammatic showing of Fig. 9indicates how this can be accomplished through hydraulic means. Fig. 9,for the sake of simplicity, only illustrates two platens of the pressand also illustrates only one belt employed in conjunction therewith,together with one set of clamping and clamping and stretching units. Thecoordinating movement of the platens and the clamping and stretchingunits is achieved by providing a two way valve 130, which is secured toany fixed part of the frame of the apparatus. An inlet pipe 131 extendsfrom the valve to any suitable supply of hydraulic pressure. A plunger132 projecting above the valve will, when dc pressed, allow thehydraulic pressure in the pipe 131 to flow through the valve 130 to theconduit 121, which extends to the hydraulic motors 38, which control thevertical movement of the clamp- Another plunger 136 is provided upon thevalve 130 and which when depressed allows the hydraulic fluid orpressure in the conduit 121 to flow to the atmosphere by way of anexhaust conduit 137. A post 139 is provided upon the upper side of thevalve 130 and serves to pivotally support a rocker arm 140, which has apan of adjustable tappets 141, which contact with the plungers 132 and136. the rocker arm 140 is secured by a suitable link 143 to the end ofa bar 144, which is pivotally supported as at 145 upon a suitableupright 146, which is fastened to the movable platen 22. The other endof the bar 144 is pivotally secured,

:- as at 148, to an upright 149 fastened to the crosshead of theclamping unit 33. The operation of this coordinating mechanism is asfollows:

Assuming the operator has clamped upon a section of belt to bevulcanized and has stretched the same, and thereafter desires to closethe platens 22 and 23 of the press together; he will now open a handvalve, which controls the flow of fluid pressure to the hydraulic motors20 and the platen 22 of the press will start upward. As soon as theplaten 22 of the press begins to move upward the upright 146 willcausean upward. movement of the bar 144 about the pivot 148, thustilting the rocker arm 146 due to the connection through the link 143.The tilting of the rocker arm 140 will compress the plunger 132, whichwill allow fluid pressure to flow through the conduit 131, the valve130, and conduit 121 to the hydraulic motors 38,..which will cause anupward movement of the clamping unit 33.

a Thusthe upward movements of the platen 22 and The end of clamping unit33 will be practically simultaneous.

As soon as the platen 22 has clamped the belt 27 against the platen 23,it will have reached the top ofits travel and further movement of theclamping. unit 33 will cause the bar 144 to pivot duit l33 to escape byway of the outlet 137. As

soon as the hydraulic pressure has been sufiiciently reduced, theclamping unit 33 will drop back veryslightly to bring the rocker arm 140substantially horizontal, in which position there will be no movement ofthe clamping unit 33, which will be substantially ona level with theplatens 22 and 23. Thus during the vulcanizing operation the belt 27will beheld flat and smooth between the platens 22 and 23, and at thesame time will be on the same horizontal plane at'both the clamping unit33 and in the press.

After the vulcanizing operation the operator will open the valvecontrolling the exhausting of the hydraulic motors 20, which will causethe lower platen 22 to begin to move away from the upper platen 2 3. Thedownward movement of the platen 22 will cause the rocker arm 140 to tipto the right to depress the plunger 136, thus allowing the fluid underpressure in the hydraulic motors 38 to escape to the atmosphere throughthe conduits 121 and 137. The clamping unit 33 will then fallpractically simultaneously to the movement of the platen 22. However,once the platen 22 has reached the bottom of its travel continuedmovement of the clamping unit 33 will bring the rocker arm 140 to thehorizontal position which will cause the closing off of the-exhaust fromthe hydraulic motors 38 to stop further movement of' the clamping unit33. The operator may now open the valve controlling the clamping of thejaws upon the belt and pull the vulcanized sec tion of the belt onthrough the press.

From the foregoing it is believed apparent that the coordinatingoperation of the clamping unit and the platens will be understood.Accordingly the coordinating operation of the clamping and stretchingunit 115 (shown in Fig. 9) with respect to the movements of the platenwill not be explained in detail, inasmuch as this movement is. the sameas that described above with respect to the clamping unit 33. Theoperation of the coordinating means has been described in conjunctionwith a single pair of platens and asingle belt, for the sake ofsimplicity. However, the adaptation of coordinating means suchasdescribed aboveto the remaining clamping unit, 110 and the clamping andstretching unit 65 of the duplex press, will be readily apparent.

1 The movements of the clamping units andthe I platens can becoordinated by mechanical means,

if so desired. Suitable means for accomplishing this result areindicated in Figs. 10' and 11', and comprise a rack 150 secured to themovable platen 22, which cooperates with a pinion 151 secured upon ashaft 152, journaled in suitable brackets Mil) 153 upon a frame 154,which sl-idably supports the corresponding vertical movement of theclamping and stretching unit 115. 1

To assist in holding the belts 27 and 23 in the stretched positionsduring the vulcanizing opera -tlon, suitable locking means may beprovided to lock the stretching means in the extended or stretchingposition so that undue strain upon the stretching mechanism will beobviated. Locking means of this type will be employed. on the stretch--'ing units 65 and 115. The locking mechanism is similar upon the twostretching means. However the'locking mechanism on the stretcher 115 haswhich blocks are provided with an indenture 161 which is adapted tocooperate with lock bars 162, which are slidably carried upon themembers 82*. One of the members 82 carries a. post 165 upon which ispivotally mounted a rocker arm 166*, which is pivotally secured as at16'? to'the lock bar 162 The other of the members 82 has a post l69*-towhich is pivotally secured a link 170, which is-pivotally secured as at171 to the other of the lock bars 162 A link 1'74 is pivotally securedas at 175 to the bar 170 and at its other end is pivotally secured as at176 to the rocker arm 166 A bar 177 ispivotally fastened, as at 1'18 tothe rocker arm 166 and is provided with a handle 180 and with a notch181, whereby the bar 177- can be pulled over a pin 182 mounted upon themember 82*. Springs 185 are provided adjacent the lock bars 162 and willserve to normally retain the lock bars 162 in the innermost or lockingposition. The locking bars 162 can be moved and held to the non-lockingposition by pulling the handle 1:30 to bring the notch 181 intoengagement with the pin 182 Similar locking mechanism may of course beprovided upon the stretching unit 65.

The operation of the apparatus is as follows:

Generally the belts 27 and 28 are made up in such long flat sections itis impossible to vulcanize more than a short section thereof at onetime,

the remaining portions of the belts being rolled up upon themselves. Nowassuming that a section of the belts has just been vulcanized and thatthe presshas been opened and the clamping and stretching means loosened,then the belts are moved longitudinally, in opposite directions, so thatnew unvulcanized sections of the belts are brought between the platens16, 22 and 23. The operatorwill now energize the clamping units 33 and110, which is accomplished by supplying fluid under pressure to thehydraulic motors l4: and 44 thus causing a downward movement of thepiston rods 45 and 45 to clamp the belts 27 and 28 between the jaws 46and 41 and the jaws 46 and 41 The hydraulic motors 83 and 83 areenergized simultaneously or shortly after the operation of the hydraulicmotors 44 and 44 The operation of the hydraulic motors 83 and 83 causesdownward movement of the piston rods 86 and 86 to clamp the belts 27 and28 between the jaws 90' and 81 and the-jaws 90 and 81 The stretchingcylinders 96 and 96 are now operated to cause an outward stretchingmovementof the jaws 90 and'8l and 90 and 81 After thebelts 2'7 and 28have thus been stretched between the units 33 and 115 and the units 110and 65, respectively, the operator is ready to close the press. To dothis he opens the valve (not shown). which allows fluid under pressureto flow to the hydraulic motors 20, which will cause the platens 2 2 and23 to begin their upward movement. The'coordinating means causingsimultaneous movement of the various units 33, 65, 110 and 115 with themovement'of the platens, which has been described above, will nowcause'a by pulling the handles 180 and 180 so thatthe notches 181 and181 will cooperate with the pins 182 and 132 to lock the lock bars, 162and 162 in the retracted position. The pressure in the hydraulic motors96 and 96 will now be relieved to allow the inward movement of thestretching means. thus relieving the tension on the belt. The operatorwill now open the interior of the hydraulic motors 44 and 44 and 83 and83 to the atmosphere and will thenpass fluid under pressure to thehydraulic motors and 50 and the motors 84 and 8%, which will cause theupward movementof the piston rods 51 and 51 and the piston rods 92 and92?, which will in turn raise the jaws 46 and 46 and the jaws and 90 tocause an unclamping or a release of the belts 27 and 28. The vulcanizedportions of the belts 2'7 and 28 can now be moved out from between theplatens and new unvulcanized sections of the belts will be broughtbeneath the platens, whereupon the operation can be repeated.

By the present invention a vulcanizing and stretching press has beenprovided in which the stretching mechanism is entirely distinct from thevulcanizing means, although coordinated therewith, so that there will beno stresses tending to mis-align the platens, and, moreover, the press,as well as the stretching means, will be easily accessible from allsides and from the ends. The vertical movement of the clamping andstretching units has been coordinated. with the vertical movementof theplatens sothat at all times the platens and the clamping and. stretching units willbe substantially on the same horizontallevel, insuring asmooth straight stretch. Meanshave been provided to maintain thebelt ina stretched condition without tension upon the stretching units.Suitable mechanism has also been employed to insure the uniform outward.and vertical movement of all moving parts of the apparatus so that no.curved or mis-shaped belts will be produced.

While the apparatus has been illustrated and described as comprising athree platen press, it will be apparent that the invention is notlimited in this respect, the various features thereof being readilyadaptable to two platen presses, or even to presses having more thanthree platens. The

coordinating mechanism for coordinating the movement of the clampingmeans and the platens can be either fluid pressure means, or mechanicalmeans.

While the various motors for operating the ends of the press. Howeverthis procedure and construction obviously need not be followed as thebelts can be moved through the press in the same direction. Again thebelts or other material molded and heat treated in the press can be ofany size and need not be of such a length that they must be vulcanizedin sections. Thus individual pieces or lengths just long enough to begripped and stretched can be handled.

It will be understood that the apparatus comprising the presentinvention can be employed to mold and heat treat substantially anyelongate article and that the description and drawings show it employedin the vulcanization of rubber conveyor belting by way of example onlyalthough the apparatus is particularly adapted for that purpose.

Although I have illustrated and described only one preferred form whichthe invention may assume, and have described that form in detail, itwill be apparent to those skilled in the art that the invention is notso limited but that various modifications may be made therein withoutdeparting from the spirit of the invention or from the scope of theappended claims.

What I claim is:

1. A vulcanizing press comprising three associated platens positioned toform two material treating stations, means for moving said platens toand away from each other, stretching means associated with each materialtreating station for stretching and holding the material to bevulcanized fiat and smooth during the vulcanizing operation, each ofsaid stretching means including two pair of relatively movable clampsand means positioned at opposite ends of the platens for moving one ofthe pairs of clamps of each stretching means.

2. A press for vulcanizing belts comprising three superimposed platens,the lower and middle platens molding one belt and the middle and upperplatens molding a second belt, a belt stretching means for each belt,each of said means including clamps mounted independently of the platensfor clamping on the belt at the ends of the platens, means mountedindependently of the platens for moving one of the clamps relativelyaway from the other to stretch the belt held therebetween, said clampmoving means being mounted at opposite ends of the platens, means formoving the platens together, means for controlling the vertical positionof the clamps, said last named means being coordinated with the movementof the platens so that the belts will be maintained in a horizontalposition and in proper alignment at all times.

3. A press for vulcanizing belts comprising three superimposed platens,the lower and middle platens molding one belt and the middle and upperplatens molding a second belt, a belt stretching means for each belt,each of said means including clamps mounted independently of the platensfor clamping on the belt at the ends of the platens, means mountedindependently of the platens for moving one of the clamps relativelyaway from the other to stretch the belt held therebetween, means forlocking said clamps in the stetching positions, said clamp moving meansbeing mounted at opposite ends of the platens, means for moving theplatens together, means for controlling the vertical position of theclamps, said last named means being coordinated with the movement of theplatens so that the belts will be maintained in a horizontal positionand in proper alignment at all times.

4. A press for vulcanizing belts comprising three superimposed platens,the lower and middle platens molding one belt and the middle and uppedplatens molding a second belt, a belt stretching means for each belt,each of said means including clamps mounted independently of the platensfor clamping on the belt at the ends of the platens, means mountedindependently of the platens and at opposite ends thereof for moving oneof the clamps relatively away from the other to stretch the belt heldtherebetween and means for moving the platens together.

5. A press for vulcanizing belts comprising three superimposed platens,the lower and middle platens molding one belt and the middle and upperplatens molding a second belt, a belt stretching means for each belt,each of said means including clamps mounted independently of the platensfor clamping on the belt at the ends of the platens, means mountedindependently of the platens for moving one of the clamps relativelyaway from the other to stretch the belt held therebetween, means forlocking the clamp-moving means in the stretching position to relievestrain thereon, means for moving the platens together, and means forcontrolling the vertical position of the clamps.

6. A press for vulcanizing belts comprising superimposed platens adaptedto mold a plurality of belts, a belt stretching means for each belt,each of said means including clamps mounted independently of the platensfor clamping on the belt at the ends of the platens, means mountedindependently of the platens for moving one of the clamps relativelyaway from the other to stretch the belt held therebetween, means formoving the platens together, fluid pressure means for controlling thevertical position of the clamps, valves for the supply of fluid to saidlast named means, and mechanical means coordinated with the movement ofthe platens to control the operation of the valve so that the belts willbe maintained in a horizontal position and in proper alignment at alltimes.

7. In combination, a pair of platens adapted to mold and heat treatmaterial, means to move the platens relatively to and from each other,means for stretching and holding the material during the molding andheating operation, fluid pressure means for moving the stretching meansin the same direction as the platens and mechanical means controlled bythe position of the platens for controlling the supply of fluid pressureto the stretcher moving means, said mechanical means coordinating themovement of the platen and stretcher moving means whereby the materialwill be held in the proper position at all times.

8. A press for vulcanizing rubberized belts including platens and meansfor stretching and holding a belt between the platens in smooth flatcondition during the cure, said stretching means including two pair ofclamping jaws extending transversely of the belt, means for moving saidjaws into clamping position, means controlling the vertical position ofsaid clamping jaws, one of said pairs of jaws being mounted forhorizontal sliding movement, means for moving said last named pair ofjaws horizontally to stretch the belt, and means for locking the jaws inthe belt stretching position thereof.

HERMAN E. MORSE.

